The present invention relates to cleaning compositions for hard surfaces. They appear to be especially well suited for use in cleaning toilets, baths, shower surrounds and other plumbing fixtures, bathroom and kitchen hard surfaces, drains and floor surfaces.
The art has developed a variety of hard surface cleaning compositions, including some which are acidic. For example, U.S. Pat. No. 5,008,030 discloses cleaning compositions that contain nonionic surfactants, a monocarboxylic acid, water, and other additives. The disclosure of this patent and of all other patents described herein are incorporated by reference as if fully set forth herein. Also, U.S. Pat. No. 5,061,393 teaches a hard surface cleaner that is a mixture of a zwitterionic surfactant, nonionic surfactant, citric acid, and various other components, and U.S. Pat. No. 5,851,980 teaches aqueous acidic liquid hard surface cleaners having nonionic surfactants, glycolic and lactic acids, N-alkyldimethyl benzyl ammonium chloride, and fragrance. Ether solvents are also taught in the last of these patents.
U.S. Pat. No. 5,061,397 also teaches hard surface cleaners with butyl cellosolve, citric acid, and colorants. Other publications describe the use of sulfamic acid, amine oxides and cellulosic thickeners and hard surface cleaners.
While these varied prior art hard surface cleaners have provided a variety of ways to clean hard surfaces, they have been limited in their ability to provide residual benefits to the surfaces being cleaned. In this regard, it is desirable to render hard surfaces that are being cleaned more resistant to becoming soiled, and to provide the surface with antimicrobial characteristics.
Chitosan is a poly D-glucosamine that has been isolated from the shells of crabs, lobsters or shrimps, or derived from chitin. Chitosan has previously been added to certain skin and hair care products, including some that contain surfactants and water. In these applications chitosan is used for its protective effects. Examples of such products include hair setting preparations, hair gels, hair mousses, styling creams, anti-dandruff preparations, hair tonics, hair rinses, skin moisturizers, deodorants and antiperspirants. See also U.S. Pat. No. 4,931,271 which describes certain problems in using chitosan in shampoos with anionic surfactants.
Chitosan has also been used in a number of other contexts. For example, U.S. Pat. No. 5,541,223 teaches that chitosan can be included in a sponge. However, Applicants believe that the art had not previously included chitosan in a hard surface cleaner.
Thus, there is a continuing need to develop hard surface cleaners which not only are effective in cleaning at the time of use, but also provide positive residual benefits to the surface that has been cleaned.